Determining a sheet size of a sheet on a sheet size determining apparatus and printing apparatus

ABSTRACT

To provide a sheet size determining apparatus capable of appropriately determining a sheet size. Specifically, a sheet size detection result is acquired by a sensor, and when there are a plurality of candidate sheet sizes corresponding to the acquired detection result, a sheet size is determined from the plurality of candidate sheet sizes in response to a setting of the operation device that indicates sheet sizes.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to a sheet size determining apparatuswhich is used in a printing apparatus or the like to determine a size ofa sheet on the basis of a detection result of a sensor.

Description of the Related Art

There is known a printing apparatus which automatically detects a sizeof a sheet set on a print sheet feeding unit.

Japanese Patent Laid-Open No. 2007-8704 describes a device which detectsa size of a sheet set on an auto-sheet feeder by an optical sensor.

However, even when the size of the sheet can be detected by aconfiguration of the sensor as described in Japanese Patent Laid-OpenNo. 2007-8704, the detected sheet may be any one of sheets such as an A4size and a letter size, whose size are not distinguished from each otherby the sensor. In such a case, the sheet size cannot be uniquelydetermined.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a sheet sizedetermining apparatus capable of appropriately determining a sheet size.

In a first aspect of the present invention, there is provided a sheetsize determining apparatus that determines a sheet size based on adetection result of a sensor, the sheet size determining apparatuscomprising: an acquisition unit configured to acquire a sheet sizedetection result obtained by the sensor; and a determination unitconfigured to, in a case where there is a plurality of candidate sheetsizes corresponding to the detection result acquired by the acquisitionunit, determine a sheet size in the plurality of candidate sheet sizesin accordance with a setting in an operation device that indicates sheetsizes.

In a second aspect of the present invention, there is provided a sheetsize determining apparatus that determines a sheet size based on adetection result obtained by a plurality of sensors, the sheet sizedetermining apparatus comprising: an operation panel configured toindicate a plurality of sheet size groups in which a plurality of sheetsizes corresponding to the same detection result obtained by a pluralityof the sensors exist.

In a third aspect of the present invention, there is provided a printingapparatus capable of determining a sheet size of a sheet set in theprinting apparatus, based on a detection result obtained by a sensor,the printing apparatus comprising: an acquisition unit configured toacquire a sheet size detection result obtained by the sensor; and adetermination unit configured to, in a case where there is a pluralityof candidate sheet sizes corresponding to the detection result acquiredby the acquisition unit, determine a sheet size in the plurality ofcandidate sheet sizes in accordance with a setting in an operationdevice that displays sheet sizes.

According to the present invention, a sheet size can be appropriatelydetermined.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments with reference to theattached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating a configuration of a printingapparatus according to an embodiment;

FIG. 2 is a view illustrating an appearance of the printing apparatus ofthe embodiment;

FIG. 3 is a diagram illustrating a correlation table between a candidatesheet size and a detection result of a sensor of the printing apparatusof the embodiment;

FIG. 4 is a view illustrating an operation panel of the printingapparatus of the embodiment;

FIG. 5 is a view illustrating a sheet selection unit of the operationpanel of the printing apparatus of the embodiment;

FIG. 6 is a diagram illustrating a sheet size group and a sheet sizetable included in the group;

FIG. 7 is a diagram showing the relationship of FIGS. 7A and 7B;

FIG. 7A is a flowchart illustrating a sheet size determining control;

FIG. 7B is a flowchart illustrating a sheet size determining control;

FIG. 8 is a diagram showing the relationship of FIGS. 8A and 8B;

FIG. 8A is a flowchart illustrating a control in the event of a sheetmismatch error of the printing apparatus;

FIG. 8B is a flowchart illustrating a control in the event of a sheetmismatch error of the printing apparatus; and

FIG. 9 is a view illustrating the sheet selection unit of the operationpanel.

DESCRIPTION OF THE EMBODIMENTS

Hereinafter, embodiments of the present invention will be described indetail with reference to the drawings.

First Embodiment

In the embodiment, a printing apparatus capable of printing an image ona print sheet will be described as an example of a sheet sizedetermining apparatus which determines a sheet size of the print sheet.

FIG. 1 is a block diagram illustrating a configuration of a printingapparatus 101 according to an embodiment of the present invention.

A CPU 901 is a processor that controls the printing apparatus 101. TheCPU 901 is connected to a program memory 903 such as a ROM and a harddisk and a data memory 904 such as a RAM via an internal bus 902. Theprogram memory 903 stores a program for controlling the printingapparatus 101. More specifically, the CPU 901 can control the printingapparatus 101 by reading a program stored in the program memory 903,loading the program onto the data memory 904, and executing the programon a work memory 905 allocated to the data memory 904. Further, an imagememory 906 can be also allocated to the data memory 904 and various datasuch as image data to be printed by the printing apparatus 101 isdeveloped on the image memory 906 by the CPU 901.

An interface control part 907 communicates with a smart device 908 suchas a smart phone via an interface under the control of the CPU 901. Forexample, the interface control part can receive a print job of aprinting object from the smart device 908 and notify status informationof the printing apparatus 101 to the smart device 908. Additionally, theinterface control part 907 may perform a communication via a wiredinterface such as a USB (Universal Serial Bus) cable or a wirelessinterface such as an infrared communication or a wireless LAN.Additionally, the smart device may be, for example, a smart phone or atablet and includes various devices such as a cellular phone.

Further, a device with which the printing apparatus 101 communicates isnot limited to the smart device 908, but may be a personal computer.Other device may be a server connected via a network, a facsimileconnected via a phone line, or a digital TV. Further, the presentinvention is not limited to a case in which a print job includes data ofa printing object. For example, the printing apparatus 101 may acquiredata of a printing object from an external device such as a server inaccordance with address information included in a print job.

A motor control part 909 controls various motors for driving a printingmechanism of the printing apparatus 101 under the control of the CPU901. Specifically, a conveyance motor 910 drives a sheet feeding roller(not illustrated), a conveying roller (not illustrated), and a sheetdischarging roller (not illustrated) constituting a sheet conveyingmechanism of the printing apparatus of the embodiment in accordance withthe control of the motor control part 909. Further, a carriage motor 911(a CR motor) drives a carriage (not illustrated) equipped with a printhead 931 in accordance with the control of the motor control part 909 sothat the carriage moves in a reciprocating manner. Thereby, the printhead 931 can scan a sheet. Further, the recovery motor 912 drives a headrecovery mechanism (not illustrated) in accordance with the control ofthe motor control part 909.

A head control part 913 controls the print head 931 in accordance withthe control of the CPU 901 to eject a printing material such as ink fromthe print head 931. The CPU 901 performs driving of both the print head931 and the conveyance motor 910 so that an image is printed on a printsheet while the print head 931 scans the print sheet. More specifically,the CPU 901 inside the printing apparatus 101 serves as a printingcontrol device and controls the print head 931 and various motorsserving as a printing mechanism so that an image is printed by theprinting mechanism.

A sensor control part 914 causes each of sensor light sourcesrespectively included in sensors 110 to 112 to be described later inFIG. 2 to emit light in accordance with the control of the CPU 901 andperforms detection of receiving of reflected light by optical sensorsrespectively included in the sensors 110 to 112. For example, the sensorcontrol part 914 acquires an output level representing the intensity ofthe light received by the optical sensor. The CPU 901 inputs an outputlevel, which is acquired by the sensor control part 914, for each of theoptical sensors respectively included in the sensors 110 to 112.Thereby, the CPU 901 can specify the sensor which receives the lightreflected from the print sheet among the sensors 110 to 112. Then, theCPU 901 can determine a size of the print sheet in response to thespecified sensor. The determining process will be described later indetail in FIGS. 7A and 7B.

A panel control part 917 controls a detection of an input to anoperation panel 103 and turning on and turning off of a lamp as will bedescribed later in FIGS. 2, 4, 5, and 7 in accordance with the controlof the CPU 901. Additionally, the operation panel 103 includes anoperation device such as a key (button) which is operated by the userand a lamp which shows information on a sheet size. For example, whenthe user operates the key (button) of the operation panel 103, aninstruction of the user is input to the panel control part 917 and theinstruction is further input to the CPU 901. Further, the panel controlpart 917 can turn on the lamp in response to the instruction of the CPU901.

A scanner control part 919 controls a scanner 920 in accordance with thecontrol of the CPU 901 to read a document placed on a document plate ofthe scanner 920 and inputs the read image thereto. Further, the scannercontrol part 919 controls the read image to be stored in the imagememory 906. A memory card control part 921 writes various data into amemory card 923 attached to a memory card slot 922 or reads various datatherefrom in accordance with the control of the CPU 901.

An encoder 924 specifies a position of the carriage when the carriagemoves along a guide rail (not illustrated).

Further, the printing apparatus 101 includes a sheet feeding traydescribed below in FIG. 2.

FIG. 2 is a diagram illustrating an appearance of the printing apparatusof the embodiment. The printing apparatus 101 includes a sheet feedingtray 102 on which a user sets print sheets (for feeding the print sheet)and the operation panel 103 which is operated by the user.

The sheet feeding tray 102 is provided with a fixed guide plate 120which serves as a position reference and as a guide for setting a sheetand is provided at the end portion of the sheet feeding tray in thewidth direction of the sheet set on the sheet feeding tray. On the otherhand, the other end portion thereof in the width direction is providedwith a guide plate 121 which is movable in the sheet width direction.When the user grips a knob provided in the guide plate 121 and moves theguide plate 121 so that the set sheet is pushed to the reference guideplate 120, a sheet feeding position can be set.

The optical sheet sensor units 110, 111, and 112 are respectivelyprovided at positions determined with reference to the position of theguide plate 120 which is used as the sheet setting reference.Accordingly, as will be described later in FIG. 3 and the like, adetermination on a candidate sheet size can be performed on the basis ofa combination of detection results of three sensors.

Additionally, the above-described example corresponds to a case wherethe sheet is set based on a reference position corresponding to one sideof the sheet feeding tray, but the reference position may be set to aso-called center reference position. In that case, one of two guideplates is moved and the other thereof is also moved in response to themoving of the one of two guide to interpose a sheet therebetween. Inthis way, a sheet position can be set at a center position of the sheetfeeding tray. In this configuration, a positional relation of threesensors is, of course, set by the positions obtained by the combinationof the detection results of three sensors described in FIG. 3.Additionally, FIG. 2 schematically illustrates the sheet sensor unit.

Each of the sheet sensor units 110, 111, and 112 includes a light sourceand an optical sensor. As for each of the sheet sensor units, if a sheetcovers the sheet sensor unit when the user sets the sheet on the sheetfeeding tray 102, light which is emitted from the light source and isreflected from the sheet is received by the optical sensor. Then, it ispossible to determine whether the sheet exists on the sheet sensor unitby checking whether the optical sensor receives light having apredetermined value or more of intensity that is regarded as lightreflected from the sheet. The CPU 901 determines the size of the sheetby determining which sheet sensor unit detects that the sheet existsthereon among the sheet sensor units 110, 111, and 112, that is,determining which sheet sensor unit detects the light having thepredetermined value or more of intensity. Hereinafter, the determiningmethod will be described below.

FIG. 3 is a diagram illustrating a relation between a detection resultobtained by three sheet sensor units and a candidate sheet sizedetermined in response to the detection result. As illustrated in FIG.3, when all of the sheet sensor units 110, 111, and 112 detect theexistence of the sheet, the sheet is roughly determined as a “largesheet.” Then, the CPU 901 determines that a candidate of the size of thesheet set on the sheet feeding tray is an A4 size or a letter size.Further, when only the sensors 111 and 112 detect the existence of thesheet, the sheet is roughly determined as a “middle sheet.” Then, theCPU 901 determines that a candidate of the size of the sheet set on thesheet feeding tray is a size of 4×6 inch or a postcard size.Furthermore, when only the sensor 112 detects the existence of thesheet, the sheet is roughly determined as a “small sheet.” Then, the CPU901 determines that the candidate of the size of the sheet set on thesheet feeding tray is an L size. In the case of the small sheet, sinceonly one size is provided in the embodiment, there is only one candidatesheet size and thus the size of the sheet can be specified uniquely.

In this way, in the case that the sheet size is roughly determined asthe “large sheet” or the “middle sheet”, a plurality of candidates existas the candidate sheet sizes. In this case in which there are aplurality of candidate sheet sizes, in the embodiment, the CPU 901 thendetermines the sheet size uniquely among these candidates on the basisof the operation of the user for the operation panel 103. Hereinafter,this process will be described in detail.

FIG. 4 is a view illustrating a configuration of the operation panel 103according to the embodiment.

The operation panel 103 includes a power button 201 which is used forpower-on and power-off of the printing apparatus 101 and a power lamp202 which is turned on when power is supplied to the printing apparatus.Further, the operation panel includes a Wi-Fi button 203 which enablesor disables a Wi-Fi function serving as a radio communication and aWi-Fi lamp 204 which is turned on when the Wi-Fi function is enabled.Further, the operation panel includes an error lamp 205 which is turnedon when a predetermined error occurs in the printing apparatus 101.

Additionally, the operation panel 103 includes a sheet settingindication part 206 which allows the user to give an instruction in thesheet size determining process and a sheet switching button 207. Thesheet setting indication part 206 and the sheet switching button 207will be described later in detail in FIG. 5. Further, the operationpanel 103 includes a stop button 208 for stopping a printing process, astart button (for color) 209 for giving an instruction for a colorprinting process, and a start button (for monochrome) 210 for giving aninstruction for a monochrome printing process.

FIG. 5 is a view specifically illustrating the error lamp 205, the sheetsetting indication part 206, and the sheet switching button 207illustrated in FIG. 4. As shown by the one-dotted chain line areas inFIG. 5, the sheet sizes are grouped in accordance with combinations ofthe candidate sheet sizes included in respective the “large sheet”, the“middle sheet”, and the “small sheet.” Specifically, a sheet size group303 having a combination of a letter size and a size of 4×6 inch and asheet size group 304 having a combination of an A4 size, a postcard sizeand an L size are separately provided. As understood from FIG. 3, thesegroups are provided such that two size candidates in each of threecandidate sheet sizes shown in FIG. 3 respectively exist in differentgroups (303 and 304). Accordingly, when the user selects any one ofthese groups, the size of the sheet can be determined uniquely by acombination of the detect results of three sensors.

Additionally, the indication of the sheet setting indication part 206 isprinted on the surface of the sheet setting indication part 206 inadvance, but may be displayed on the display panel if necessary.

Further, in the sheet setting indication part 206, Reference Numeral 301indicates a sheet size group lamp which can show that the sheet sizegroup 303 is active and Reference Numeral 302 indicates a sheet sizegroup lamp which can show that the sheet size group 304 is active. Thesheet switching button 207 is a button for switching the sheet sizegroup.

FIG. 6 is a diagram illustrating the sheet size group. In the examplesillustrated in FIGS. 3 and 5, the sheet size group 303 and the sheetsize group 304 illustrated in FIG. 6 are separately provided. The usercan select the group 303 or the group 304 by pressing the sheetswitching button 207. A lamp which corresponds to a selected group isturned on among the lamps 301 and 302.

FIGS. 7A and 7B are flowcharts illustrating a process of determining thesize of the sheet set on the sheet feeding tray according to theembodiment.

The process illustrated in FIGS. 7A and 7B is performed when theprinting apparatus 101 is activated. The printing apparatus 101 stores“final selection sheet size” which is finally selected by the userthrough the selection of the group 303 or 304 illustrated in FIG. 5 foreach of the large sheet and the middle sheet, and which is determined bythe sheet sensor unit, in a non-volatile memory (the program memory 903or the like) of the apparatus body. Specifically, the “A4 size” or the“letter size” is stored as the “final selection sheet size”corresponding to the large sheet and the “size of 4×6 inch” or the“postcard size” is stored as the “final selection sheet size”corresponding to the middle sheet.

It should be noted that the “final selection sheet size” is not storedwhen the printing apparatus 101 is activated for the first time.Therefore, in STEP 612, the CPU 901 determines whether the printingapparatus 101 is activated for the first time. In the case of the firstactivation, in STEP 613, the CPU 901 stores an initial value of the“final selection sheet size” in the non-volatile memory (the programmemory 903 or the like) in accordance with the setting of a destinationset in the printing apparatus 101 in advance. Here, since the sheet sizeis set uniquely in the case of the small sheet (size: L), the “finalselection sheet size” corresponding to the small sheet may not bestored.

All lamps of the sheet size groups are turned off in a state where thesheet is not set on the apparatus. When the sheet is just set on thesheet feeding tray in this state, the sheet sensor unit detects thesheet (Yes in STEP 601). Then, when the CPU 901 determines that thedetermination result corresponds to a plurality of candidate sheet sizes(the large sheet and the middle sheet) (Yes in STEP 602), a processproceeds to STEP 603. In STEP 603, the CPU 901 specifies a sheet amongthe “large sheet” and the “middle sheet” on the basis of the detectionresult obtained by the sensors. Then, the CPU 901 reads the “finalselection sheet size” which is stored in the non-volatile memory andcorresponds to the specified detection result (the large sheet or themiddle sheet) and sets it as a determination sheet size (hereinafter,referred to as a current sheet size) that is finally determineduniquely. For example, it is assumed that the user selects the group 303illustrated in FIG. 5 in advance before the print sheet is set on theprinting apparatus 101. In this case, as illustrated in FIGS. 5 and 6,the “final selection sheet size” corresponding to the large sheet is the“letter size” and the “final selection sheet size” corresponding to themiddle sheet is the “size of 4×6 inch.” Thus, in STEP 603, when acombination of the detection results of the sensors corresponds to the“large sheet”, the CPU 901 reads the letter size which is the “finalselection sheet size” corresponding to the large sheet. This size is setas the current sheet size. Next, the lamp of the sheet size groupincluding the current sheet size is turned on (STEP 605).

Meanwhile, when the detection result of the sheet sensor unit specifiesthe sheet size uniquely (the small sheet size), the CPU 901 sets thecorresponding sheet size (L) as the current sheet size (STEP 604). Then,the lamp corresponding to the sheet group (in this case, the group lamp302) is turned on (STEP 605).

When the CPU 901 detects a removing the sheet set on the sheet feedingtray 102 by the sheet sensor unit (Yes in STEP 606), the CPU 901 turnoff the lamp of the sheet size group (STEP 607) and causes the routineto return to a state before the setting of the sheet (STEP 601).

When the sheet switching button 207 is operated while the sheet is set(Yes in STEP 608), the CPU 901 determines whether a state having aplurality of candidate sheet sizes (the large sheet and the middlesheet) exist or a state in which the candidate sheet size is determineduniquely (the small sheet) (STEP 609). In the former state, in STEP 610,the CPU 901 sets a candidate sheet size included in a plurality ofcandidate sheet sizes and included in a group selected from the group303 and the group 304 illustrated in FIGS. 5 and 6, as the current sheetsize. For example, as in the above-described example, a case is assumedsuch that the determination result obtained by the sheet sensor unit isthe “large sheet”, the group selected before the sheet switching buttonis operated is the group 303, and the current sheet size is the lettersize. In this case, in STEP 610, the A4 size which is the sheet sizeincluded in the group 302 which is a group after the sheet switchingbutton is operated and included in the candidate sheet size (the A4 sizeand the letter size) is set as the current sheet size.

Then, the CPU 901 stores a new current sheet size among the “largesheet” and the “middle sheet” as a “final sheet setting size”corresponding to the current sheet size and selectively turns on thelamp (STEP 611). At this time, the “final sheet setting size”corresponding to the other size among the “large sheet” and the “middlesheet” is not changed.

FIGS. 8A and 8B are flowcharts illustrating a control by the printingapparatus when the printing apparatus receives a print job from a hostdevice such as a PC or a smart phone in the embodiment. It should benoted that the current sheet size at this time is stored in the programmemory 903 or the like.

When the CPU 901 receives a print job from the host device (Yes of STEP701), it is determined whether the current sheet size corresponding tothe size of the sheet set on the sheet feeding tray 102 is same as thesheet size designated by the print job (STEP 702). When it is determinedthat both sheet sizes match each other, the CPU 901 starts a process ofprinting an image corresponding to the print job by a printing part ofthe printing apparatus 101 (STEP 703).

Meanwhile, when the CPU 901 determines that both sheet sizes do notmatch each other in STEP 702, it is determined that a “sheet mismatcherror” occurs and the error lamp 205 and the sheet size group lamp (301or 302) corresponding to the sheet size designated by the print job aremade to blink (STEP 704).

Accordingly, it is possible to notify information on whether the sheetgroup needs to be switched by the sheet switching button to the user.

Next, the CPU 901 determines whether one of a case that the user removesthe sheet from the sheet feeding tray (the sheet sensor unit detects asheet removed state), a case that the sheet sensor unit detects thesetting of the sheet, or a case that the sheet switching button 207 isoperated (STEP 705) occurs.

When it is determined that any one of the above-described cases occurs,the CPU 901 performs the sheet size determining process illustrated inFIGS. 7A and 7B (STEP 706). Here, the error lamp and the group lamp ofSTEP 704 are continued to blink on a priority basis in a state where thesheet mismatch error of STEP 704 occurs (STEP 706). For example, whenthe user selects a group which corresponds to a group lamp differentfrom a blinking group lamp of a group (a group of a designated size),the selected group lamp is turned on while the blinking is continued.Further, when the user selects a group which corresponds to the samegroup lamp as the blinking group lamp of the group (a group of adesignated size), the lamp may blink while not being turned oncontinuously.

When the CPU 901 detects an operation of the start button (208 or 210)in this state, it is determined whether the current sheet size matchesthe sheet size designated by the print job again (STEP 708). When bothsheet sizes match each other, the CPU 901 cancels the sheet mismatcherror (stops the blinking of the lamp) and starts the printing process(STEP 709). When both sheet sizes do not match each other, the CPU 901determines whether an image may be printed to an area beyond the sheetby comparing the printing areas of the current sheet size and the sizedesignated by the print job. In the process of FIGS. 8A and 8B, the CPU901 performs printing of an image at an equal magnification in responseto the size designated by the print job. For that reason, for example,when the current sheet size is smaller than the designated size, it isdetermined that an image is printed to an area beyond the sheet.

When it is determined that an image is printed to an area outside thesheet, an error is not canceled and the process proceeds to STEP 712. InSTEP 712, the CPU 901 determines whether the stop button (210) isoperated. Then, when the operation is detected, the job is canceled andthe printing process is not performed (an error is also canceled) (STEP713).

Meanwhile, in STEP 710, when it is determined that an image is notprinted to an area outside the sheet, the CPU 901 cancels an error andperforms printing of data of a size designated by a print job on acurrently set sheet (STEP 711).

Second Embodiment

FIG. 9 is a view illustrating a sheet setting indication part 206according to a second embodiment of the invention.

As described above in the first embodiment, when a sheet is set on thesheet feeding tray 102, three levels of determination are made by thesensor units provided in the sheet feeding tray in order to determinewhether a set sheet is the large sheet, the middle sheet, or the smallsheet. However, the letter size and the A4 size cannot be distinguishedfrom each other in the case of the determination of the large sheet andthe size of 4×6 inch and the postcard size cannot be distinguished fromeach other in the case of the determination of the middle sheet.Additionally, the L size can be specified only in the case of thedetermination of the small sheet.

Therefore, the operation panel of the embodiment includes lamps 911,912, 921, and 922 which show what size of the sheet is selected amongcandidate sheet sizes in each of groups when the sensor unit determinesthat a current sheet is the large sheet or the middle sheet, and alsoincludes switching buttons 901 and 902. Additionally, since the L sizeis determined uniquely in the case of the determination of the smallsheet, a lamp or a button thereof is not provided.

Additionally, in FIG. 9, when a size of 10×15 cm also corresponds to the“small sheet”, lamps and a switching button may be further provided tocorrespond to the L size and the size of 10×15 cm as the size candidate.

In the example of FIG. 5, the user selects the sheet size through theselection of a combination 303 (the letter size, the size of 4×6 inch,and the size of 10×15 cm) or a combination 304 (the A4 size, thepostcard size, and the L size) of the sheet sizes respectively includedin the “large sheet”, the “middle sheet”, and the “small sheet.”Meanwhile, in FIG. 9, the switching button (901, 902) is provided foreach of the “large sheet” and the “middle sheet” and thus the sheet sizecan be separately selected.

In FIG. 9, a button is provided for each of the “large sheet” and the“middle sheet” and a lamp is provided for each of the sheet sizesrespectively included in the “large sheet” and the “middle sheet”.Meanwhile, in the example illustrated in FIG. 5, since an option for thesheet size is small compared to the example illustrated in FIG. 9, thenumber of the lamps or the buttons can be limited. Accordingly, it ispossible to suppress an increase in cost due to an increase in size ofthe apparatus or an increase in number of the components.

According to the above-described embodiment, the size of the sheet seton the sheet feeding tray of the printing apparatus is determined by theoperation of the user and the detection result obtained by the sensor.Accordingly, the size of the sheet can be appropriately determined.

In addition, when the host device transmits a print job having a sheetsize which is different from the sheet size determined as describedabove, this difference can be expressed by a combination of lightning odthe lamps on the operation panels. Accordingly, an operation ofcanceling or continuing the printing process can be appropriately andfast performed by the user.

With such a configuration, for example, even when an LCD or a touchpanel is not provided in the printing apparatus, the sheet can beswitched by operations of the lamps and the buttons. Further, since thesheet size which is finally determined for each determination of thesensor is stored in the printing apparatus, the number of times ofoperating the button can be decreased.

Additionally, according to the above-described embodiments, the printsheet to be used for the printing process has been described as thesheet of which the size needs to be determined, but the invention is notlimited thereto. For example, the size of the document read by thescanner 920 may be determined.

Further, the sheet size determining apparatus of the embodiment has beendescribed by exemplifying the printing apparatus, but the invention isnot limited thereto. For example, an external device connected to theprinting apparatus or the scanner may serve as the sheet sizedetermining apparatus which determines the size of the sheet set on theprinting apparatus or the size of the sheet set on the scanner. In thatcase, the sheet size can be determined in such a manner that thedetection result of the sensor provided in the printing apparatus or thescanner is acquired and setting information of the operation panelprovided in the printing apparatus or the scanner serving as an externaloperation device is acquired.

Further, in the above-described embodiments, the size of the sheet seton the sheet feeding tray provided at the rear face of the printingapparatus is determined, but the invention is not limited thereto. Thesize of the sheet provided at the lower portion of the printingapparatus may be determined or the size of the sheet fed to the printingapparatus may be determined. In the latter case, for example, when asensor is provided on the carriage equipped with the print head 931 anda plurality of candidate sheet sizes are detected by the sensor, thesheet size may be specified uniquely in response to the content selectedin the panel as in the above-described embodiments.

Additionally, the function of the embodiment can be also realized by thefollowing configuration. That is, the function of the embodiment can bealso realized in such a manner that a program code for executing theprocess of the embodiment is supplied to a system or an apparatus and acomputer (or a CPU or MPU) of the system or the apparatus executes theprogram code. In this case, the program code read out from a storagemedium realizes the function of the above-described embodiments and thestorage medium storing the program code also realizes the function ofthe embodiment.

Further, the program code for realizing the function of the embodimentmay be executed by one computer (CPU, MPU) or may be executed by acooperation of a plurality of computers. Further, the program code maybe executed by a computer or hardware such as a circuit for realizing afunction of the program code may be provided. Alternatively, a part ofthe program code may be realized by hardware and the rest thereof may beexecuted by a computer.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2016-042868 filed Mar. 4, 2016, which is hereby incorporated byreference wherein in its entirety.

What is claimed is:
 1. A sheet size determining apparatus comprising: atleast one processor; a sensor mechanism which detects a candidate sizegroup, among a first candidate size group and a second candidate sizegroup, of a sheet set on the sheet size determining apparatus; anoperation mechanism on which a user designates a sheet size in each ofthe first candidate size group and the second candidate size group,wherein the operation mechanism indicates a first indicated group whichincludes a size in the first candidate size group and a size in thesecond candidate size group, and indicates a second indicated groupwhich includes another size in the first candidate size group andanother size in the second candidate size group, and the operationmechanism includes two lamps for the first indicated group and thesecond indicated group, and wherein the designation of the sheet sizefor each of the first candidate size group and the second candidate sizegroup is performed on the operation mechanism by a selection of thefirst indicated group or the second indicated group; and a memory whichstores a first sheet size designated on the operation mechanism for thefirst candidate size group and a second sheet size designated on theoperation mechanism for the second candidate size group, wherein the atleast one processor stores the first sheet size on the memory,regardless of the second sheet size stored for the second candidate sizegroup on the memory, wherein the at least one processor determines, as asheet size of the sheet set on the sheet size determining apparatus, acurrent sheet size which is included in the candidate size groupdetected by the sensor mechanism and is stored on the memory for thedetected candidate size group, and wherein, based on a determinationthat the sheet size which is designated by a print job does notcorrespond to the current sheet size, the operation mechanism operates alamp corresponding to an indicated group which includes the sheet sizedesignated by the print job.
 2. The sheet size determining apparatusaccording to claim 1, wherein the operation mechanism includes aswitching button, and wherein a sheet size group selected by theselection from the first indicated group and the second indicated groupis switched by the switching button.
 3. The sheet size determiningapparatus according to claim 1, wherein the sensor mechanism includes aplurality of sensors and detects the candidate size group based onwhether or not each of the plurality of sensors detects the sheet set onthe sheet size determining apparatus.
 4. The sheet size determiningapparatus according to claim 2, wherein the operation mechanismemphasizes an indicated group out of the first indicated group and thesecond indicated group which includes a sheet size stored on the memoryfor the candidate size group detected by the sensor mechanism, andwherein, in a case where the switching button is operated when theoperation mechanism emphasizes the indicated group, the at least oneprocessor determines another sheet size in the candidate size groupdetected by the sensor mechanism, as the current sheet size.
 5. Thesheet size determining apparatus according to claim 4, wherein, in acase where the switching button is operated when the operation mechanismemphasizes the indicated group, the at least one processor stores theanother sheet size on the memory, for the candidate size group detectedby the sensor mechanism.
 6. The sheet size determining apparatusaccording to claim 4, wherein, in a case where the switching button isoperated when the operation mechanism emphasizes the indicated group,the operation mechanism emphasizes another indicated group.
 7. The sheetsize determining apparatus according to claim 4, wherein the operationmechanism emphasizes an indicated group, by turning on a lampcorresponding to the indicated group.
 8. The sheet size determiningapparatus according to claim 4, wherein in a case where the sensormechanism detects that a sheet is set on the sheet size determiningapparatus, the operation mechanism emphasizes an indicated group.
 9. Thesheet size determining apparatus according to claim 1, wherein when itis determined that the sheet size which is designated by the print jobdoes not correspond to the current sheet size, the operation mechanismmakes a lamp corresponding to the indicated group which includes thesheet size designated by the print job, to blink.
 10. A printingapparatus comprising: at least one processor; a sensor mechanism whichdetects a candidate size group, among a first candidate size group and asecond candidate size group, of a sheet set on the printing apparatus;an operation mechanism on which a user designates a sheet size in eachof the first candidate size group and the second candidate size group,wherein the operation mechanism indicates a first indicated group whichincludes a size in the first candidate size group and a size in thesecond candidate size group, and indicates a second indicated groupwhich includes another size in the first candidate size group andanother size in the second candidate size group, and the operationmechanism includes two lamps for the first indicated group and thesecond indicated group, and wherein the designation of the sheet sizefor each of the first candidate size group and the second candidate sizegroup is performed on the operation mechanism by a selection of thefirst indicated group or the second indicated group; a memory whichstores a first sheet size designated on the operation mechanism for thefirst candidate size group and a second sheet size designated on theoperation mechanism for the second candidate size group; and a printingmechanism which prints an image on the sheet set on the printingapparatus, wherein the at least one processor stores the first sheetsize on the memory, regardless of the second sheet size stored for thesecond candidate size group on the memory, wherein the at least oneprocessor determines, as a sheet size of the sheet set on the printingapparatus, a current sheet size which is included in the candidate sizegroup detected by the sensor mechanism and is stored on the memory forthe detected candidate size group, and wherein, in a case where a printjob to which a sheet size is designated is received by the printingapparatus, the at least one processor determines whether or not thesheet size which is designated by the print job corresponds to thecurrent sheet size, wherein, in a case where it is determined that thesheet size which is designated by the print job corresponds to thecurrent sheet size, the printing mechanism print an image correspondingto the print job, and wherein, based on a determination that the sheetsize which is designated by the print job does not correspond to thecurrent sheet size, the operation mechanism operates a lampcorresponding to an indicated group which includes the sheet sizedesignated by the print job.
 11. The printing apparatus according toclaim 10, wherein the operation mechanism includes a switching button,and wherein a sheet size group selected by the selection from the firstindicated group and the second indicated group is switched by theswitching button.
 12. The printing apparatus according to claim 11,wherein the operation mechanism emphasizes an indicated group out of thefirst indicated group and the second indicated group which includes asheet size stored in the memory for the candidate size group detected bythe sensor mechanism, and wherein, in a case where the switching buttonis operated when the operation mechanism emphasizes the indicated group,the at least one processor determines another sheet size in thecandidate size group detected by the sensor mechanism, as the currentsheet size.
 13. The printing apparatus according to claim 12, wherein,in a case where the switching button is operated when the operationmechanism emphasizes the indicated group, the at least one processorstores the another sheet size on the memory, for the candidate sizegroup detected by the sensor mechanism.
 14. The printing apparatusaccording to claim 12, wherein, in a case where the switching button isoperated when the operation mechanism emphasizes the indicated group,the operation mechanism emphasizes another indicated group.
 15. Theprinting apparatus according to claim 12, wherein the operationmechanism emphasizes an indicated group, by turning on a lampcorresponding to the indicated group.
 16. The printing apparatusaccording to claim 15, wherein, when it is determined that the sheetsize which is designated by the print job does not correspond to thecurrent sheet size, the operation mechanism makes a lamp correspondingto the indicated group which includes the sheet size designated by theprint job, to blink.
 17. The printing apparatus according to claim 16,wherein the operation mechanism continues to make the lamp to blink,regardless of an operation to the switching button.
 18. The printingapparatus according to claim 10, wherein the sensor mechanism includes aplurality of sensors and detects the candidate size group based onwhether or not each of the plurality of sensors detects the sheet set onthe printing apparatus.
 19. The printing apparatus according to claim10, wherein, in a case where it is determined that the sheet size whichis designated by the print job is smaller than the sheet size of thesheet set on the printing apparatus, the printing mechanism prints animage having a size corresponding to the sheet size designated by theprint job.
 20. A sheet size determining method by an apparatus whichcomprises at least one processor, a sensor mechanism which detects acandidate size group, among a first candidate size group and a secondcandidate size group, of a sheet set on the apparatus, an operationmechanism on which a user designates a sheet size in each of the firstcandidate size group and the second candidate size group, and a memorywhich stores a first sheet size designated on the operation mechanismfor the first candidate size group and a second sheet size designated onthe operation mechanism for the second candidate size group, the methodcomprising: storing, by the at least one processor, the first sheet sizeon the memory, regardless of the second sheet size stored for the secondcandidate size group on the memory; determining, by the at least oneprocessor, as a sheet size of the sheet set on the apparatus, a currentsheet size which is included in the candidate size group detected by thesensor mechanism and is stored on the memory for the detected candidatesize group, wherein the operation mechanism indicates a first indicatedgroup which includes a size in the first candidate size group and a sizein the second candidate size group, and indicates a second indicatedgroup which includes another size in the first candidate size group andanother size in the second candidate size group, and the operationmechanism includes two lamps for the first indicated group and thesecond indicated group, designating the sheet size for each of the firstcandidate size group and the second candidate size group on theoperation mechanism by a selection of the first indicated group or thesecond indicated group, and wherein, based on a determination that thesheet size which is designated by a print job does not correspond to thecurrent sheet size, the operation mechanism operates a lampcorresponding to an indicated group which includes the sheet sizedesignated by the print job.
 21. A sheet size determining apparatuscomprising: at least one processor; a sensor mechanism which detects acandidate size group, among a first candidate size group and a secondcandidate size group, of a sheet set on the sheet size determiningapparatus; an operation mechanism on which a user designates a sheetsize in each of the first candidate size group and the second candidatesize group, wherein the operation mechanism indicates a first indicatedgroup which includes a size in the first candidate size group and a sizein the second candidate size group, and indicates a second indicatedgroup which includes another size in the first candidate size group andanother size in the second candidate size group, and the operationmechanism includes two lamps for the first indicated group and thesecond indicated group, and wherein a selection of the first indicatedgroup or the second indicated group is performed on the operationmechanism; and wherein the at least one processor determines, as a sheetsize of the sheet set on the sheet size determining apparatus, a currentsheet size which is included in the candidate size group detected by thesensor mechanism and an indicated group selected on the operationmechanism from the first indicated group and the second indicated group,and wherein, based on a determination that the sheet size which isdesignated by the print job does not correspond to the current sheetsize, the operation mechanism operates a lamp corresponding to anindicated group which includes the sheet size designated by the printjob.
 22. The sheet size determining apparatus according to claim 21,wherein if a sheet of any size in the first candidate size group is seton the sheet size determining apparatus, a result of detection by thesensor mechanism is the same and the first candidate size group isdetected, and if a sheet of any size in the second candidate size groupis set on the sheet size determining apparatus, a result of detection bythe sensor mechanism is the same and the second candidate size group isdetected.
 23. The sheet size determining apparatus according to claim21, wherein when it is determined that the sheet size which isdesignated by the print job does not correspond to the current sheetsize, the operation mechanism makes a lamp corresponding to theindicated group which includes the sheet size designated by the printjob, to blink.
 24. The sheet size determining apparatus according toclaim 21, wherein the first indicated group includes letter size in thefirst candidate size group and 4×6 size in the second candidate sizegroup, and the second indicated group includes A4 size in the firstcandidate size group and hagaki size in the second candidate size group.